small block oil priming question

Make sure you get oil to both heads. Covers off. For the shaft, yes one “book” way. How can it cause issues not doing it that way? The vacuum canister can interfere/hit other things when trying to timing it if you just drop it in. One tooth off isn’t much, but you would be surprised how quickly you run out of real estate around the distributor. Also, if you haven’t and it is not a roller, make sure the lifters are turning as you turn it over by hand.